# include <fcntl.h>
# include <unistd.h>
# include <stdlib.h>
# include <stdio.h>


int main (int argc, char **argv)
{
    int             fd, ctl, i;
    char            buff[5];

    if (argc < 2)
    {
        write (STDOUT_FILENO, "missing an arg\n", 16);
        return -1;
    }

    if ( 0 > (fd=open(argv[1], O_RDWR, 0666)) )
    {
        perror ("open");
        return -1;
    }
    
    for (i = 0; i < 52;)
    {
        if (0 > (ctl = read (fd, buff, 5)))
        {
            perror ("read");
            return -1;
        }
        write (STDOUT_FILENO, buff, 5);
        write (fd, "_", 1);
        i = i + 6;
    }

    while (-1 == close(fd));

    return 0;

}
